[Mister Pontiac]

Case study, if you will. My 71 GTO (400/400) was in dire need of some radiator work. Since the weather is back in the triple digits every day here in Phoenix, and I drive the car every day, it was beyond time to fix the problem.

I started down the old road, looking for someone to either Rod out or ReCore my original, but wasn't having a lot of luck as it was a Saturday and time was of the essence.

On a whim, I checked what might be available from my local O'Reilly's. I found a replacement unit (link below) in the aluminum/plastic configuration, which kind of surprised me. But even more than that, the $120 price tag really caught my eye. Oh sure, I figured it's probably China junk, but for $120, it can't be worse than my clogged up original. Let's give it a shot. Maybe it will get me thru the summer or until I can get my original back up to snuff.

To say I'm impressed is an understatement. In every driving condition, the car is now running 15-20 degrees cooler than before. Absolutely no other changes. Heck, I test drove the car the very next day, under the exact same conditions (104-105 degrees ambient) to prove the point. Yes, the radiator was working that much better. In fact, even the 'feel like' temperature under the hood is noticeably cooler. There's just not a 30 lb block of metal up there holding in all that heat anymore. Not only does the aluminum dissipate the heat so much better, the plastic tanks are cool enough I can actually touch them. There's no 'instant burn' like you would get if you touched a copper/brass unit.

Now granted, my original is just that. Old, leaking, and fairly clogged up though I've power flushed it several times. Nevertheless, the difference was impressive.

So, this brings me to my next question... how long do these units last? I realize all of the newer cars use this type construction in their radiators, so I have to believe the combo has staying power.

Am I missing something? Is there a reason (aside from aesthetics) that more guys aren't running these? Obviously for those with an eye for originality or a true restoration, these are out of the question. But for a driver like mine? Boy, I can't see a downside here.

Here's the link to the Murray 68-72 crossflow that I just installed. Oh, and this was a week back, and I've since driven the car hundreds of miles, in all kinds of conditions. I still can't get it above 205-208 (the original would have been 225 under the same conditions), and at moderate speeds, it runs right on the thermostat even in 100 degree heat. Pretty amazing contrast to me.

https://www.oreillyauto.com/detail/b...radiator&pos=0

[389]

Look at the Champion. I buy them on e-Bay, never had any issues with them. I've bought quite a few of them too..

[Mister Pontiac]

Yep, I'm very familiar with the Champions too. I've run several of those in the past as well. But those weren't available locally either, and I really wanted to get something done that day.

I'm also thinking that since those are 100% aluminum (all metal like others), I believe the plastic tanks are another step of improvement over even pure aluminum. Those plastic tanks stay so cool by comparison, and that helps to lessen the "heat sink" under the hood. I'm thinking these combo units are the design leader at the moment. Believe me, I was as surprised as anyone.

[ZeGermanHam]

There's nothing wrong with an aluminum radiator with plastic end-tanks. They certainly live a normal lifespan in modern cars as OEM equipment. Can't speak for the quality of your specific make/model, however. The radiator in my BMW is known for blowing the end tanks as they age, so people in the E36 BMW world tend to replace their radiators every 10 years or 100k miles, whichever is first, as preventive maintenance. Not a big deal, as an OEM BMW radiator is only around $160.

As for why more people aren't using the exact radiator you linked to in their GTOs, I'd think it has more to do with the fact that you can buy a full aluminum radiator that looks much more like the originals. You get the advantages of having a more modern radiator, but without the plastic tanks to distract the eye. And with these cars, many or most of us are trying to achieve a specific look under the hood, and aren't necessarily chasing the lowest dollar part that works well. But if you don't mind now it looks, and it works well, there's certainly nothing wrong with that.

[Chief of the 60's]

Its now running cooler to you because by your own admission your old radiator was shot. https://www.hotrod.com/articles/ccrp...-for-your-car/

[Mister Pontiac]

Originally Posted by ZeGermanHam

There's nothing wrong with an aluminum radiator with plastic end-tanks. They certainly live a normal lifespan in modern cars as OEM equipment. Can't speak for the quality of your specific make/model, however. The radiator in my BMW is known for blowing the end tanks as they age, so people in the E36 BMW world tend to replace their radiators every 10 years or 100k miles, whichever is first, as preventive maintenance. Not a big deal, as an OEM BMW radiator is only around $160.

As for why more people aren't using the exact radiator you linked to in their GTOs, I'd think it has more to do with the fact that you can buy a full aluminum radiator that looks much more like the originals. You get the advantages of having a more modern radiator, but without the plastic tanks to distract the eye. And with these cars, many or most of us are trying to achieve a specific look under the hood, and aren't necessarily chasing the lowest dollar part that works well. But if you don't mind now it looks, and it works well, there's certainly nothing wrong with that.

Thanks Ze. I'm happy to hear the Beemer crowd is seeing 100k without much issue on these designs. That's essentially what I was asking as the only real unknown to me on the combo units was their longevity.

I agree that a lot of guys like the look of originality, and I completely get that. In other cars in my fleet, I tend to prefer a more original look as well. But that's what gets me here. Of all the aftermarket aluminum radiators I've used over the years, many with a ribbed (ala) OEM look to them, I think this plastic/aluminum unit is actually closer to that OEM look than those other units were. The tanks have very similar 'ribs' if you will, to the original Harrison tanks, and to the casual observer, I'm not sure how many would notice. With the aluminum units, I've had to paint the ribbed tanks at a minimum just to draw the eye away from them, and even with that, I don't know that they look any more OEM than this plastic/aluminum unit does. Very surprising. I'm wondering if they've simply 'upped the game' on design as well with these new radiators as I haven't paid attention to these units before. The hobby marches on.

Originally Posted by Chief of the 60's

Its now running cooler to you because by your own admission your old radiator was shot. https://www.hotrod.com/articles/ccrp...-for-your-car/

Chief, as usual, you're only seeing half the picture. I've replaced many a radiator in my day, including many that were just as shot as this one, but I've never had a replacement make such an immediate impact as this new radiator. It's a combination of factors. Yes, it's new. But it also has a much more compact fin arrangement, many more tubes, and now, different material combinations. In other words, it's an improvement over simply cleaning and reinstalling an original. I've been there, done that, many times, and I can assure you that had I simply cleaned out the original core, it would not be running as cool as this aftermarket unit is running. This is a sharp contrast, and marked improvement to the old days.

[chrisp]

That is a excellent find & the results are what count / lifetime warranty is a bonus / the price even in Pa. $120.99 free shipping . As far as original looking not many out there concerned & those that are use original not aluminum. I think it is great & their website shows all of the other Pontiac / Chevy -vehicles it fits as well .

[Ccass]

The $120 parts store radiator can be a perfect solution for any given owner. However, here is why everyone doesn't run out and buy a $120 radiator.

1. It doesn't look original enough. Also, these radiators aren't even available for most pre-1968 vehicles.
2. Shrouds and other attaching parts don't line up all the time. Modifications have to be made to make extra parts fit properly.
3. the capacity is a lot less than the more expensive radiators. Many owners are upgrading their motors with many new high tech components. These components may lead to generating some extra heat and cause the $120 radiator to not only fail to cool properly but also cause the radiator to prematurely fail.
4. You can't compare the quality of a $120 plastic tank radiator to the quality of an OEM Late Model plastic tank radiator.
5. A plastic tank $120 radiator is held together with epoxy. When the epoxy starts to dry rot, the radiator will start weeping. Once that happens, the car will start running hotter and soon you need a new radiator or you are risking a very untimely failure.

[PontiacJim1959]

I think most "newer" cars use the aluminum/plastic tanks. I have found on the smaller 4-cyl cars that around 150K is a good mileage to toss it out and install a new one, $60-$80 seems about what I pay at the local store.

I am one for keeping an eye on my gauges and know where the temp gauge indicates when the radiator/cooling system is working well. When it begins to climb up a tad, and knowing my mileage, I just replace the radiator and hoses. I do this myself, fairly easy to do.

If the T-stat is on its way out, it'll heat up fast/boil over, so you know that has gone south on you. Bad head gasket, well, water in the oil or once in my Toyota, oil filling the radiator and pushing out without any water in the oil - gasket let go on a coolant hole right next to the oil feed in the block and the oil pressure won over the coolant pressure.

I am also one who does flush and add new coolant to my cooling system as anti-freeze does break down. I figure this has got to help with some of the natural corrosion/oxidization that takes place in the cooling system.

I have also used Champion as they are reasonably priced and do the job. But as pointed out, some want original looks and the ability to fit the factory shroud. The 2 core aluminum, depending on tube size and spacing, can do a better job than a 3/4 core original style radiator and be much lighter in weight.

So if it works for you, and it seems to have, go with it. Might last a lifetime.

[Mister Pontiac]

Originally Posted by Ccass

The $120 parts store radiator can be a perfect solution for any given owner. However, here is why everyone doesn't run out and buy a $120 radiator.

1. It doesn't look original enough. Also, these radiators aren't even available for most pre-1968 vehicles.
2. Shrouds and other attaching parts don't line up all the time. Modifications have to be made to make extra parts fit properly.
3. the capacity is a lot less than the more expensive radiators. Many owners are upgrading their motors with many new high tech components. These components may lead to generating some extra heat and cause the $120 radiator to not only fail to cool properly but also cause the radiator to prematurely fail.
4. You can't compare the quality of a $120 plastic tank radiator to the quality of an OEM Late Model plastic tank radiator.
5. A plastic tank $120 radiator is held together with epoxy. When the epoxy starts to dry rot, the radiator will start weeping. Once that happens, the car will start running hotter and soon you need a new radiator or you are risking a very untimely failure.

Chris, I think you've identified what I was after here. I appreciate your response.

I agree with you on a lot of these points, and I do love your Cold Case Radiators as well (ran one in my 72 LeMans for years and was very happy with it).

To your points, I will agree that this is a model year limited item, and something I was unaware of until I found out about them on an spur of the moment search. In my case, it fit in the factory location without any modification, but I realize that's not everyone's situation. And true enough, the capacity is less in this radiator than the factory (and other aftermarket radiators), but that doesn't seem to be a problem in stock application. With higher HP motors, I can see how it may not be enough.

I'm most curious about your points 4 & 5 as these are my main concerns. I can see how the units are sealed with epoxy, and mechanically squeezed and held together (aluminum tabs on the core bent around the tanks mating surfaces), and I really do wonder if these units are using sub-par epoxy with a short life span vs an OEM late model radiator. If so, that's a very valid point of consideration, and another reason they are less expensive. I will be curious to see what kind of longevity I get from this unit.

Mainly, I'm curious about the different materials. As I mentioned, I noticed how much 'cooler' the tanks are at operating temperature vs an all metal radiator. I assume that has to do with the heat retention of the plastic vs the metal, but either way, it is a marked difference. Reducing underhood heat soak would be another important item I would think in maintaining a cooler running engine.

Have you investigated building these combo unit designs in your Cold Case line? I'm wondering what your conclusions would be after studying this idea.

[Ccass]

Originally Posted by Mister Pontiac

Have you investigated building these combo unit designs in your Cold Case line? I'm wondering what your conclusions would be after studying this idea.

We have considered the idea but we considered it with Pypes as well. We decided that we just don't want to get into the 'replacement' market. There is no real noticeable advantage of one over another. Therefore we can't add value. All that matters in 'crash parts' market is price. If it falls apart in 6 months, the seller doesn't care. He gets to sell another one! It's also a very different set of distribution channels. Super high volume low margins. For those reasons, we have kept true to our roots and have always stayed focused on providing products that have very good value in the performance market.

[dataway]

I'd agree that for a daily driver a modern cheapo radiator is a perfectly fine solution. The key point being price. But keep in mind, it doesn't work a smidge better, and probably worse than a proper recored original.

You probably would have seen an even more dramatic decrease in temps with a recored original. But then your price-per-degree temp drop would have been much higher

Remember, the plastic tanks feel cooler because they are HOLDING IN the heat, not because they are running cooler ... plastic is a heat insulator, aluminum and copper are heat conductors. So while certainly more comfortable to the touch, they are less efficient ... but then the heat should be removed by the core ... not the tanks, so plastic is fine.

As opposed to the $530 I spent to recore my original to maintain originality ... $120 sounds very attractive.

[LATECH]

Originally Posted by 389

Look at the Champion. I buy them on e-Bay, never had any issues with them. I've bought quite a few of them too..

I put a champion in my 64 10 years ago.Best move ever.
Still is just fine.

Brass does not shed heat anywhere near as well as aluminum, FACT. An original radiator is an obsolete part , but for originality ,I get it.

[dataway]

Aluminum has about twice the thermal conductivity of cartridge brass. (tanks)

However the original cores are made of copper, which has twice the thermal conductivity of aluminum.

https://neutrium.net/heat_transfer/t...ls-and-alloys/

Radiators were changed to aluminum for two reasons, WAY less expensive than copper, and WAY lighter. The downside is, aluminum has about twice the expansion rate, so a lot more stress on seams, they require more surface area per BTU, and corrosion ... while there are people running around in cars with 40 year old original radiators, I'd venture to guess that most aluminum radiators would be hard pressed to last 20 years.

That said, aluminum certainly has it's place, good all around material for a heat exchanger, cheap, light, easy to fabricate, good thermal properties compared to most metals and looks nice.

['ol Pinion head]

Originally Posted by dataway

Aluminum has about twice the thermal conductivity of cartridge brass. (tanks)

However the original cores are made of copper, which has twice the thermal conductivity of aluminum.

https://neutrium.net/heat_transfer/t...ls-and-alloys/

Radiators were changed to aluminum for two reasons, WAY less expensive than copper, and WAY lighter. The downside is, aluminum has about twice the expansion rate, so a lot more stress on seams, they require more surface area per BTU, and corrosion ... while there are people running around in cars with 40 year old original radiators, I'd venture to guess that most aluminum radiators would be hard pressed to last 20 years...

The Chinese had a huge effect on the cost of all copper products, huge cost increases beginning in the early 00's with spun copper product. In the mid to late 90's, I had a local radiator shop recore several original Harrison 4 core radiators for high level restoration use. The cost out the door was $150 a radiator. By '03, that same cost had doubled. A few years later, that recore cost had more than trippled!

First negative experience I had with an plastic & aluminum radiator was little over 25 years ago in my previous '89 4.0 Cherokee. By then, the little workhorse had a little over a 100k miles & I was replacing hoses as part of preventative maintainance. One of the radiator hoses would not come off after I unclamped it. Cut a slit in the end of the hose along the outlet, & it still wouldn't come off. Pulled a little harder, & ended up breaking the outlet off the plastic tank radiator... not the result I was after. Went to local radiator shop & ordered from their warehouse a brass tank, copper core replacement. That copper core radiator cooled perfectly & went another 180k plus miles til the XJ was totaled, sideswiped by a Semi. Am sure the initial cost of the plastic/alum construction radiator saved Chrysler a few bucks, but not a design I had much appreciation for. No way, I'd buy a cheesy plastic tank alum core radiator & install it in one of my A or F-body's. An all aluminum radiator is in the cards for the '63 LeMans build.

[dataway]

If you look at when radiators made an almost universal change to aluminum ... it was right around the time people were stealing copper out of houses for sale, and electrocuting themselves trying to steal copper from electrical substations. Yep .. right around 20 years ago.

In age where they don't even make pennies out of copper, they are not going to make radiators out of copper Strangely enough, the price has gone down in the last few years ... but nothing like it was in the early 2000's.

2001 copper 0.64 cents per pound
2006 copper $3.82 per pound
Currently about $2.50 per pound.

[FrankieT/A]

Not one person mentioned the plastic tanks split. The first thing that happens is the strengthening ribs crack and the tank just splits from the thermo cycles as the tanks expand and contract along with the plastic gets brittle.

[Formulajones]

I don't really trust the plastic tank radiators. Something about a radiator epoxied together doesn't give me a warm fuzzy feeling.

I went with a Cold Case in one of our classic daily drivers (actually 2 cars now with them) and just can't beat the price point and quality when I look at other aluminum radiators I've bought (2 Griffins and one B Cool) for twice the price that don't cool any better. So I really don't mind ~$350-$400 for a good radiator. In comparison that still cheap to me. Best part is the tanks still have a stock appearance so when painted most don't even notice, but more importantly the stock shrouds fit without modifications and nothing needs to be done to the core support either.

As far as temp differences, I did a ton of testing last year on dad's car with an excellent quality desert cooler 4 core copper and compared that to a Cold Case 2 core with surprising results considering he has an engine that will push the cooling system limits in the Arizona heat. I wrote about it on here somewhere. Tried all kinds of stuff with that thing and found the stock parts (ie: shroud, clutch fan) worked the best, along with the Cold Case radiator. Can't get that thing over 170 degrees now in the AZ heat, most of the time it runs around at 165 or less, actually runs cooler idling in traffic than it does on the highway, lol. It's nice to drive it and not have to worry about temps anymore.

I also, as I briefly mentioned above, installed a Cold Case in one of our classic daily drivers late last year. I removed the original 3 core copper dated Dec 68, that was actually still working perfectly fine. The car never got over 185 in 100+ temps and traffic. I figured it was time I should replace it now and save it for a restoration later.
However now with the Cold Case stock style replacement, the temps have dropped a solid 10 degrees. We've been 98 degrees so far this year and even idling in a drive through for 10-15 minutes it never got over 175. Going down the road it's 168-170. The rest of the cooling system is just stock stuff, shroud, clutch fan, etc.... Pretty impressed with the quality and price point of these things.

[LATECH]

One more point I want to mention here that copper is better at conducting heat than aluminum, but aluminum is able to radiate the heat into the air better than copper because of its lower density.
The best practical coolers have a copper base, usually heat-pipes, and aluminum fins. Copper is better at heat transfer and aluminum is better at heat dissipation, so good heat-sinks have a copper base that quickly/efficiently gets the heat away from whatever is being cooled.

My champion all aluminum.

Plastic tanks have come a LONG ways from the 90s also.They still split,crack , deteriorate, but nothing lasts forever

[lust4speed]

My Bounder motorhome with the Ford chassis came with plastic end tanks. The motorhome was 4 years old when the first radiator started leaking at the crimped seam. Replaced it with the same model Ford radiator and that one lasted three years. Looked back a few years in the parts book and found a copper radiator. It was still doing fine when I sold the motorhome sixteen years later. So my experience with the plastic tanks wasn't good. The expansion and contraction of the aluminum on the lesser expanding plastic tanks caused both of the failures. I'll take tanks and cores made of the same material.